The falling dart tester determines the impact resistance of plastic film by the free falling dart method. The apparatus establishments the energy required to tear film specimens under specified conditions of impact of a free falling dart. The energy is expressed in terms of the weight of a dart 50% if the film specimens fail under the conditions specified. A range of weight is provided to be performed on various film thickness. The working range of the weight is estblished by finding the weight that will just break the sample film.